InRoads V8i SS1 File Formats

Greetings-

I'm just double-checking...

1.  It appears the DTM and ALG formats have changed for InRoads SS1, correct?  That is, unless saved down, a DTM or ALG created in InRoads SS1 won't be readable by an earlier version of Inroads? 

2.  If that's the case, I'm curious what changed (or is now saved) that is now saved with those filetypes. 

3. ITL and IRD fiels are XML based, and thus the same format applies from InRoads 8.7 through SS1? 

Thanks much,

Jeff